1. Field of the Invention
This invention relates to a novel additive composition for use in motor fuels. The additive comprises the reaction product obtained by reacting a lactone with an alkylphenoxypolyoxyalkylene amine to produce a motor fuel-soluble alkylphenoxypolyoxyalkylene amine lactone compound which provides a number of valuable properties in a motor fuel composition.
The combustion of a hydrocarbon motor fuel in an internal combustion engine leads to the formation and accumulation of deposits on various parts of the combustion chamber as well as on the fuel intake and exhaust system of the engine. The presence of deposits in the combustion chamber seriously reduces the operating efficiency of the engine. First, deposit accumulation within the combustion chamber inhibits heat transfer between the chamber and the engine cooling system. This leads to higher temperatures within the combustion chamber, resulting in increases in the end gas temperature of the incoming charge. Consequently, end gas auto-ignition occurs causing engine knock. In addition, the accumulation of deposits within the combustion chamber reduces the volume of the combustion zone, causing a higher than design compression ratio in the engine. This, in turn, can also lead to engine knocking. A knocking engine does not effectively utilize the energy of combustion. Moreover, a prolonged period of engine knocking can cause stress fatigue and wear in pistons, connecting rods, bearings and cam rods of the engine. The phenomenon noted is characteristic of gasoline powered internal combustion engines. It may be overcome by employing a higher octane gasoline which resists knocking for powering the engine. This need for a higher octane gasoline as mileage accumulates has become known as the engine octane requirement increase (ORI) phenomenon. It is particularly advantageous if engine ORI can be substantially reduced or eliminated by preventing or modifying deposit formation in the combustion chambers of the engine.
Another problem common to internal combustion engines is the formation of intake valve deposits. Intake valve deposits interfere with valve closing and eventually will lead to valve burning. Such deposits interfere with valve motion and valve seating and tend to reduce the volumetric efficiency of the engine and to limit the maximum design power. Valve deposits may be produced from thermally and oxidatively unstable fuel or from lubricating oil oxidation products. The hard carbonaceous deposits produced collect in the tubes and runners that are part of the exhaust gas recirculation (EGR) flow. These deposits are believed to be formed from exhaust particles which are subjected to rapid cooling while mixing with the air-fuel mixture. Reduced EGR flow can result in engine knock and in nitric oxide, NO.sub.x, emission increases. It would therefore be desirable to provide a motor fuel composition which minimizes or overcomes the formation of intake valve deposits.
An object of this invention is to provide a novel additive reaction product which may be employed in fuel compositions and particularly in a motor fuel composition.
Another object is to provide a fuel additive reaction product and a motor fuel composition which inhibits the formation of intake valve deposits in an internal combustion engine.
Another object of this invention is to provide a fuel additive and a fuel composition which inhibits or reduces the formation of combustion chamber deposits in an internal combustion engine.
Yet another object of this invention is to provide a concentrate composition which may be added to a motor fuel to provide motor fuel compositions of the instant invention.